Lamp



FIG. 1 is a bottom perspective view of a lamp showing my design;

FIG. 2 is a front elevational view thereof, the rear, left and right elevational views thereof being the same due to symmetry;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a bottom plan view thereof.

Broken lines represent boundaries which form no part of the claimed design. 

CLAIM The ornamental design for a lamp, as shown and described. 